Method of producing platelets

• US 6,732,961 B2
• Filed: 11/15/2001
• Issued: 05/11/2004
• Est. Priority Date: 11/16/2000
• Status: Expired due to Term

• Current Assignee: Sicpa Holding SA
• Original Assignee: Consortium fuer Elektrochemische Industrie GmbH (Dr. Alexander Wacker Familiengesellschaft Mit Beschrã¤Nkter Haftung)
• Inventors: Leigeber, Horst, Kreuzer, Franz-Heinrich, Stanjek, Volker, Gurtner, Adolf
• Primary Examiner(s): Rosenbaum, Mark
• Application Number:
  US10/002,923
• Publication Number:
  US 20020086113A1
• Time in Patent Office: 908 Days
• Field of Search: 241/30, 241/5, 241/1, 241/26, 241/301, 241/24.28, 241/3
• US Class Current: 241/3
• CPC Class Codes: C09B 67/0061 by grinding a dyed resin
• CPC Class Codes: C09B 67/0098 Organic pigments exhibiting interference colours, e.g. nacrous pigments
• CPC Class Codes: C09K 19/38 Polymers
• CPC Class Codes: C09K 19/3852 Poly(meth)acrylate derivatives
• CPC Class Codes: C09K 19/3866 containing steroid groups
• CPC Class Codes: C09K 19/586 Optically active dopants; chiral dopants

Abstract

The invention relates to a method of producing platelets, wherein a material to be processed into platelets is applied in a flowable or gaseous state to a substrate, consolidated, removed from the substrate, and subjected to a crushing or grinding process, wherein the material is applied to the substrate in succeeding layers such that after application, a lamina pack is present which, in cross section perpendicular to its surface, has individual laminae of a thickness of between 0.2-1000 μm, and said lamina pack, having been stripped from the substrate, is treated in such a way that the material disintegrates into individual laminae and the individual laminae are reduced in size to a particle size of 0.5-10000 μm.

Claims

1. In a method of producing platelets, wherein a material to be processed into platelets is applied in a flowable or gaseous state to a substrate, is consolidated, removed from the substrate and subjected to a crushing or grinding process, the improvement comprising applying one or a plurality of materials in succeeding layers to said substrate to prepare a lamina pack which in cross section perpendicular to its surface, contains a plurality of individual, separable laminae of a thickness of between 0.2-1000 μ

m, stripping said lamina pack from the substrate, disintegrating said lamina pack into individual laminae, and reducing the individual laminae in size to a mean particle size of 0.5-10,000 μ

m.

2. The method of claim 1, wherein the lamina pack is prepared by applying and consolidating the material to be processed three or more times.

3. The method of claim 1, wherein the material to be processed comprises polymerizable and/or crosslinkable liquid-crystalline, optionally cholesteric, materials.

4. The method of claim 1 wherein at least one of said separable laminae comprises a plurality of non-separable layers.

5. The method of claim 1, wherein the material to be processed into platelets comprises at least one material selected from the group consisting of polyesters, epoxy resins, vinyl esters, vinyl ethers, polyurethanes, silanes, siloxanes, silanolates, water glass, silicic acid esters, liquid-crystalline polymerizable and/or crosslinkable aromatic, cycloaliphatic or heterocyclic compounds, film-forming dispersions, resin solutions, suspensions, powder paints, substances which can be applied by sputtering or vapor deposition, polymerizable substances, polyaddable substances, hydrosilylable substances, polycondensable substances, crosslinkable substances, fusible resins, thermoplasts, solutions which can be converted into films by the evaporation of solvents, suspensions, compositions which can be converted into two-phase systems by polymerization, and mixtures thereof.

6. The method of claim 1, wherein the lamina pack is prepared by repeated application of one or more materials to be processed into platelets onto a substrate in the form of a sheet without a release agent or release layer.

7. The method of claim 1, wherein the lamina pack is prepared by application of the material to be processed into platelets onto a substrate in the form of a rotating cylinder and is released in the form of a roll-shaped or an annular lamina pack.

8. The method as claimed in claim 7, wherein the material to be processed into platelets is first applied to a revolving belt and is then transferred to said rotating cylinder, so that a lamina pack in the form of a roll is produced on the cylinder.

9. The method as claimed in claim 7, wherein the material to be processed into platelets is applied to the inside of said rotating cylinder, such that a lamina pack in the form of a roll-shaped or an annular lamina pack is produced on the inside of the cylinder.

10. The method of claim 1, wherein the lamina pack is produced continuously by an applicator mechanism revolving in a circular orbit and the lamina pack takes the form of a helix.

11. The method of claim 1, wherein the lamina pack is produced continuously by an applicator mechanism moving back and forth in a plane and the lamina pack takes the form of a folded-leaf structure.

12. The method of claim 1, wherein the lamina pack is produced with the use of a release agent.

13. The method of claim 1, wherein at least one of said laminae is produced in the presence of an auxiliary which aligns liquid crystals, or in the presence of an electric or magnetic field.

14. The method of claim 1, wherein the lamina packs are produced with the use of smoothing elements.

15. The method of claim 1, wherein laminae are continuously removed from the lamina pack on the side opposite an applicator mechanism.

16. The method of claim 1, wherein size reduction of the laminae is carried out in an edge mill, a ball mill, a pin mill or an air-jet mill, and the material is then classified.

17. The method of claim 1, wherein materials having different characteristics are applied on top of one another immediately after one another to form a multiple layer laminate, with the proviso that the layers of said multiple layer laminate are bonded firmly together and represent individual laminae of the lamina pack being formed which, during the grinding process, form platelets having a desired laminar sequence.